Ships Cover for submarines of the E class (1912-1916), F class (1915-1916), G class (1915-1917), J class [including J7] (1915-1917), K class (1916-1917), L class (1917), L9 class (1918-1919), L50 class (1918-1919), M class (1917-1918), S class (1914), and a few preliminary papers for the design that became the Rainbow class (1930). In addition to the broad classes the following individual submarines are also represented: HMS K26 (1919), HMS Nautilus (1914), HMS Oberon (1926), HMS Swordfish (1916), and HMS X1 (1923). The mix of documents is very eclectic and in some instances quite fragmentary, but general themes which dominate are details of fittings and equipment, reports on foreign submarine designs, with particular focus on the US, German and Imperial Japanese Navies, reports of manoeuvreing trials by British submarines, correspondence relating to torpedoes and torpedo tubes, papers on ASDIC and anti-submarine warfare, living conditions aboard submarines, and a number of discussion papers on experimental work. The earliest document dates from August 1914 and the last from December 1925.